Sea waves are composite waves that are a combination of different kinds of regular waves, but they are not completely irregular and have spectrum structures in which most energy is concentrated around regular waves of a specific height and frequency. Using such characteristics, sea waves are converted into regular waves of the same period as that of the center of the spectrum. The response of wave-power generation with respect to the regular waves of specified wave height and frequency is checked using antenna theory. A method of commercialization has been discovered that makes reference to the above behavior of the response. There is a close correspondence between wave-power generation and the antenna. The antenna theory can be used as an effective tool when researching wave-power generation.
The problem is that sea waves are not regular. The waveform of sea waves is distorted with respect to that of a sine wave. The wave height and wave length are also not constant. However, in terms of statistics, the wave nature can be obviously read from the sea waves. Further, if the mean value is paid attention to, there is regularity between the wave height and the wave period. For this reason, sea waves are regarded as semi-regular waves and as a kind of wave motion which continuously varies within a regular pattern. Therefore, with regard to wave-power generation, if parameters of a generation apparatus are adjusted (optimized) in response to variation of characteristics attributable to the irregularity of the sea waves, that is, in response to a variation in conditions, satisfactory power generation can be automatically maintained. For this, development of a controller for wave-power generating apparatuses that can reduce the cost of power generation is required.